Selective isoprene hydrogenation over LnNi (Ln=Pr, Gd, Tm) intermetallic compounds

Isoprene hydrogenation on LnNi (Ln=Pr, Gd, Tm) rare earth intermetallic com pounds has been studied. The effect of rare earth elements on nickel cataly tic behaviour was investigated. The results at steady state indicate that t he compounds are all more active than pure nickel. The main reaction produc ts are 2M2B (2-methyl-2-butene) and 2M1B (2-methyl-1-butene) with a selecti vity greater than 90%. The activity at t(o) (initial time reaction) and the selectivity at isoprene isoactivity clearly indicate the promotion of nick el's catalytic behaviour by the rare earth element. (C) 2001 Elsevier Scien ce B.V. All rights reserved.